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Pre-Pleistocene fossils of Anolis lizards are rare, although 20 Miocene fossils preserved in amber from the island of Hispaniola have been reported on previously. Using light-microscopy and computed-tomography imaging, we studied a new amber fossil Anolis lizard from Hispaniola. The fossil is likely a juvenile and preserves a largely intact left forelimb, including both scales and skeletal elements, as well as some additional skin, skin impressions, and fragmentary skeletal elements from other parts of the body. Using measurements and lamella counts from the forelimb of the fossil and other juvenile anoles, discriminant function analysis and three Euclidean-distance criteria derived from a principal components analysis consistently support classification of the fossil as a member of the trunk ecomorph category, and those results, in combination with two scale characters preserved in the fossil, suggest that it is a member of the Anolis distichus series within the Ctenonotus clade. These results represent only the third case of a well-supported assignment of an Anolis fossil to the trunk ecomorph category and the first to the A. distichus series. They also highlight that such assignments can sometimes be inferred from highly incomplete fossils. [ABSTRACT FROM AUTHOR]

Uncovering convergent and divergent patterns of diversification is a major goal of evolutionary biology. On four Greater Antillean islands, Anolis lizards have convergently evolved sets of species with similar ecologies and morphologies (ecomorphs). However, it is unclear whether closely related anoles from Central and South America exhibit similar patterns of diversification. We generated an extensive morphological data set to test whether mainland Draconura -clade anoles are assignable to the Caribbean ecomorphs. Based on a new classification framework that accounts for different degrees of morphological support, we found morphological evidence for mainland representatives of all six Caribbean ecomorphs and evidence that many ecomorphs have also evolved repeatedly on the mainland. We also found strong evidence that ground-dwelling anoles from both the Caribbean and the mainland constitute a new and distinct ecomorph class. Beyond the ecomorph concept, we show that the island and mainland anole faunas exhibit exceptional morphological convergence, suggesting that they are more similar than previously understood. However, the island and mainland radiations are not identical, indicating that regional differences and historical contingencies can lead to replicate yet variable radiations. More broadly, our findings suggest that replicated radiations occur beyond island settings more often than previously recognized. [ABSTRACT FROM AUTHOR]